In wireless networks, mobile nodes (MNs) can move between, for example, access points (APs), sub-networks, and/or networks. When a MN moves out of the range of a first AP and enters the range of a second AP, a handoff from the first AP to the second AP can occur. These handoffs can be, for example, layer 2 (L2) handoffs and/or layer 3 (L3) handoffs. Moving from one AP to another can also involve an authentication process, between, for example, an MN and a network it is joining. The amount of time consumed by handoffs and authentication can slow down or interrupt traffic being sent to and from a, for example, MN when it moves from one network to another. Such interruptions can be especially problematic for real-time applications, such as, for example, voice-over-internet-protocol (VoIP) communications and streaming video, where the interruption can be noticeable to the user.
In some cases, the time needed by an MN to perform an L2 handoff can be on the order of a few hundred milliseconds, which can cause a noticeable interruption in, for example, an ongoing real-time multimedia session. Additionally, for example, in either open 802.11 networks or 802.11 networks with Wired Equivalent Privacy (WEP) enabled, scanning can contribute to over 90% of the total handoff time. In some systems, such as, for example, in 802.11 networks with either WPA or 802.11i enabled, the authentication process can dominate the handoff delay. This can be because data may not be exchanged among MNs before authentication completes. For example, using 802.1x, during authentication, only Extensible Authentication Protocol Over Local Area Network (EAPOL) traffic may be exchanged with a supplicant (e.g., a node attempting authenticate with an AP).
When an MN moves from one network to another, sometimes the MN can be required to obtain a new address, such as, for example, an IP address. This can be the case during, for example, an L3 handoff. New IP addresses can be obtained using, for example, Dynamic Host Configuration Protocol (DHCP). However, this can take up to, for example, one second, which can be long enough to cause a disruption in, for example, a video chat using an IP connection.